title: Dynamic tissue analysis using time- and wavelength-resolved fluorescence spectroscopy for atherosclerosis diagnosis.
abstract: Simultaneous time- and wavelength-resolved fluorescence spectroscopy (STWRFS) was developed and tested for the dynamic characterization of atherosclerotic tissue ex vivo and arterial vessels in vivo. Autofluorescence, induced by a 337 nm, 700 ps pulsed laser, was split to three wavelength sub-bands using dichroic filters, with each sub-band coupled into a different length of optical fiber for temporal separation. STWRFS allows for fast recording/analysis (few microseconds) of time-resolved fluorescence emission in these sub-bands and rapid scanning. Distinct compositions of excised human atherosclerotic aorta were clearly discriminated over scanning lengths of several centimeters based on fluorescence lifetime and the intensity ratio between 390 and 452 nm. Operation of STWRFS blood flow was further validated in pig femoral arteries in vivo using a single-fiber probe integrated with an ultrasound imaging catheter. Current results demonstrate the potential of STWRFS as a tool for real-time optical characterization of arterial tissue composition and for atherosclerosis research and diagnosis.
authors.affiliation: Department of Biomedical Engineering, University of California Davis, Davis, CA 95616, USA.
authors.forename: Yinghua
authors.initials: Y
authors.lastname: Sun
authors.forename: Yang
authors.initials: Y
authors.lastname: Sun
authors.forename: Douglas
authors.initials: D
authors.lastname: Stephens
authors.forename: Hongtao
authors.initials: H
authors.lastname: Xie
authors.forename: Jennifer
authors.initials: J
authors.lastname: Phipps
authors.forename: Ramez
authors.initials: R
authors.lastname: Saroufeem
authors.forename: Jeffrey
authors.initials: J
authors.lastname: Southard
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Elson
authors.forename: Laura
authors.initials: L
authors.lastname: Marcu
mesh_terms: D000818:Animals; D050197:Atherosclerosis / Q000175:diagnosis*; D004867:Equipment Design; D019544:Equipment Failure Analysis; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012815:Signal Processing, Computer-Assisted / Q000295:instrumentation*; D013050:Spectrometry, Fluorescence / Q000295:instrumentation*; D013552:Swine